. "nitrogen cycle"@en-us . . "113522084"^^ . . "nitrogen cycle"^^ . "0"^^ . "the circulation of nitrogen; nitrates from the soil are absorbed by plants which are eaten by animals that die and decay returning the nitrogen back to the soil"@en-us . . . "112758466"@en-us . "0"^^ . . "13522084-n"^^ . . . .